1. Field of the Invention
The present invention relates generally to read/write magnetic head assemblies, and more particularly to devices for shielding and canceling unwanted electromagnetic fields within such heads.
2. Description of the Prior Art
In a conventional hard-disk drive (HDD) utilizing so-called MR heads as the recording transducer, the recording head typically uses different elements on the head to perform the write and read operations. Writing on the hard-disk is typically performed using an inductive writing head element, and reading back from the hard-disk is typically performed using a read head having a magnetoresistive (MR) element. The inductive write head element and the MR element are specially-made structures on the read/write head consisting of layers of specially-deposited thin films. The MR element layers are typically deposited onto the substrate first, and the inductive-element layers are deposited after the deposition of the MR element. Significantly, the write head element and the read head element cannot operate at the same time due to interference of the electromagnetic field generated by the write signal with the read-back signal. In other prior art devices the inductive element layers are deposited first and the MR element layers are deposited after them. However, interference between the write signal and the read-back signal still exists, and these devices also cannot simultaneously write to and read from the disk.
There are significant uses in the industry for a read/write head that has the ability to simultaneously write data to a disk and read data from a disk. However, prior art read/write heads cannot perform this task due to the write signal electromagnetic field interference described above. There is therefore a need for a read/write head wherein the writing function and reading function can be simultaneously performed.
The present invention is a read/write head for writing information to magnetic media and reading information from magnetic media. It includes a write head element for writing information onto magnetic media, a read head element for reading information from the magnetic media, and an electromagnetic field shield element that is disposed between the write head element and the read head element. The electromagnetic field shield functions to shield the read head from electromagnetic field energy created by the write head element to reduce the total electromagnetic field that the read head element is exposed to during a writing operation. An enhanced second embodiment includes an electrical circuit element that is disposed proximate the read head element that functions to generate an electromagnetic field at the read head element that is generally oppositely directed to the electromagnetic field generated by the write head element. The method for operating the read/write head in a hard disk drive, includes the steps of writing data onto a hard disk and reading data from the hard disk simultaneously with the data writing. This is accomplished by shielding the read head from the electromagnetic field energy generated during the data writing by utilizing the electromagnetic field shield element that is disposed between the write head element and the said read head element. The electrical circuit element of the second embodiment is preferably interconnected with the write head electric circuit.
It is an advantage of the present invention that the functions of writing data and reading data can be simultaneously performed.
It is another advantage of the present invention that the electromatic field shield element shields the read head from the electromagnetic field generated by the write head element, such that signal interference of the read head element is minimized.
It is a further advantage of the present invention that an interference reduction electrical circuit element may be disposed proximate the read head element to generate an electromagnetic field that interferes with an electromagnetic field from the write head element.
It is yet another advantage of the present invention that an improved read/write head has been developed which utilizes existing manufacturing technology.
It is yet a further advantage of the present invention that an improved slider having the improved read/write head disposed thereon, and an improved hard disk drive are made possible through the utilization of the present invention.
These and other features and advantages of the present invention will become fully understood upon reading the following detailed description of the preferred embodiments which makes reference to the several figures of the drawings.